1 //===-- include/flang/Evaluate/type.h ---------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #ifndef FORTRAN_EVALUATE_TYPE_H_
10 #define FORTRAN_EVALUATE_TYPE_H_
11
12 // These definitions map Fortran's intrinsic types, characterized by byte
13 // sizes encoded in KIND type parameter values, to their value representation
14 // types in the evaluation library, which are parameterized in terms of
15 // total bit width and real precision. Instances of the Type class template
16 // are suitable for use as template parameters to instantiate other class
17 // templates, like expressions, over the supported types and kinds.
18
19 #include "common.h"
20 #include "complex.h"
21 #include "formatting.h"
22 #include "integer.h"
23 #include "logical.h"
24 #include "real.h"
25 #include "flang/Common/Fortran.h"
26 #include "flang/Common/idioms.h"
27 #include "flang/Common/real.h"
28 #include "flang/Common/template.h"
29 #include <cinttypes>
30 #include <optional>
31 #include <string>
32 #include <type_traits>
33 #include <variant>
34
35 namespace Fortran::semantics {
36 class DeclTypeSpec;
37 class DerivedTypeSpec;
38 class ParamValue;
39 class Symbol;
40 bool IsDescriptor(const Symbol &);
41 } // namespace Fortran::semantics
42
43 namespace Fortran::evaluate {
44
45 using common::TypeCategory;
46
47 // Specific intrinsic types are represented by specializations of
48 // this class template Type<CATEGORY, KIND>.
49 template <TypeCategory CATEGORY, int KIND = 0> class Type;
50
51 using SubscriptInteger = Type<TypeCategory::Integer, 8>;
52 using CInteger = Type<TypeCategory::Integer, 4>;
53 using LogicalResult = Type<TypeCategory::Logical, 4>;
54 using LargestReal = Type<TypeCategory::Real, 16>;
55
56 // A predicate that is true when a kind value is a kind that could possibly
57 // be supported for an intrinsic type category on some target instruction
58 // set architecture.
59 // TODO: specialize for the actual target architecture
IsValidKindOfIntrinsicType(TypeCategory category,std::int64_t kind)60 static constexpr bool IsValidKindOfIntrinsicType(
61 TypeCategory category, std::int64_t kind) {
62 switch (category) {
63 case TypeCategory::Integer:
64 return kind == 1 || kind == 2 || kind == 4 || kind == 8 || kind == 16;
65 case TypeCategory::Real:
66 case TypeCategory::Complex:
67 return kind == 2 || kind == 3 || kind == 4 || kind == 8 || kind == 10 ||
68 kind == 16;
69 case TypeCategory::Character:
70 return kind == 1 || kind == 2 || kind == 4;
71 case TypeCategory::Logical:
72 return kind == 1 || kind == 2 || kind == 4 || kind == 8;
73 default:
74 return false;
75 }
76 }
77
78 // DynamicType is meant to be suitable for use as the result type for
79 // GetType() functions and member functions; consequently, it must be
80 // capable of being used in a constexpr context. So it does *not*
81 // directly hold anything requiring a destructor, such as an arbitrary
82 // CHARACTER length type parameter expression. Those must be derived
83 // via LEN() member functions, packaged elsewhere (e.g. as in
84 // ArrayConstructor), or copied from a parameter spec in the symbol table
85 // if one is supplied.
86 class DynamicType {
87 public:
DynamicType(TypeCategory cat,int k)88 constexpr DynamicType(TypeCategory cat, int k) : category_{cat}, kind_{k} {
89 CHECK(IsValidKindOfIntrinsicType(category_, kind_));
90 }
DynamicType(int k,const semantics::ParamValue & pv)91 constexpr DynamicType(int k, const semantics::ParamValue &pv)
92 : category_{TypeCategory::Character}, kind_{k}, charLength_{&pv} {
93 CHECK(IsValidKindOfIntrinsicType(category_, kind_));
94 }
95 explicit constexpr DynamicType(
96 const semantics::DerivedTypeSpec &dt, bool poly = false)
97 : category_{TypeCategory::Derived}, derived_{&dt} {
98 if (poly) {
99 kind_ = ClassKind;
100 }
101 }
CONSTEXPR_CONSTRUCTORS_AND_ASSIGNMENTS(DynamicType)102 CONSTEXPR_CONSTRUCTORS_AND_ASSIGNMENTS(DynamicType)
103
104 // A rare use case used for representing the characteristics of an
105 // intrinsic function like REAL() that accepts a typeless BOZ literal
106 // argument and for typeless pointers -- things that real user Fortran can't
107 // do.
108 static constexpr DynamicType TypelessIntrinsicArgument() {
109 DynamicType result;
110 result.category_ = TypeCategory::Integer;
111 result.kind_ = TypelessKind;
112 return result;
113 }
114
UnlimitedPolymorphic()115 static constexpr DynamicType UnlimitedPolymorphic() {
116 DynamicType result;
117 result.category_ = TypeCategory::Derived;
118 result.kind_ = ClassKind;
119 result.derived_ = nullptr;
120 return result; // CLASS(*)
121 }
122
AssumedType()123 static constexpr DynamicType AssumedType() {
124 DynamicType result;
125 result.category_ = TypeCategory::Derived;
126 result.kind_ = AssumedTypeKind;
127 result.derived_ = nullptr;
128 return result; // TYPE(*)
129 }
130
131 // Comparison is deep -- type parameters are compared independently.
132 bool operator==(const DynamicType &) const;
133 bool operator!=(const DynamicType &that) const { return !(*this == that); }
134
category()135 constexpr TypeCategory category() const { return category_; }
kind()136 constexpr int kind() const {
137 CHECK(kind_ > 0);
138 return kind_;
139 }
charLength()140 constexpr const semantics::ParamValue *charLength() const {
141 return charLength_;
142 }
143 std::optional<Expr<SubscriptInteger>> GetCharLength() const;
144 std::optional<Expr<SubscriptInteger>> MeasureSizeInBytes(
145 FoldingContext * = nullptr) const;
146
147 std::string AsFortran() const;
148 std::string AsFortran(std::string &&charLenExpr) const;
149 DynamicType ResultTypeForMultiply(const DynamicType &) const;
150
151 bool IsAssumedLengthCharacter() const;
152 bool IsNonConstantLengthCharacter() const;
153 bool IsTypelessIntrinsicArgument() const;
IsAssumedType()154 constexpr bool IsAssumedType() const { // TYPE(*)
155 return kind_ == AssumedTypeKind;
156 }
IsPolymorphic()157 constexpr bool IsPolymorphic() const { // TYPE(*) or CLASS()
158 return kind_ == ClassKind || IsAssumedType();
159 }
IsUnlimitedPolymorphic()160 constexpr bool IsUnlimitedPolymorphic() const { // TYPE(*) or CLASS(*)
161 return IsPolymorphic() && !derived_;
162 }
GetDerivedTypeSpec()163 constexpr const semantics::DerivedTypeSpec &GetDerivedTypeSpec() const {
164 return DEREF(derived_);
165 }
166
167 bool RequiresDescriptor() const;
168 bool HasDeferredTypeParameter() const;
169
170 // 7.3.2.3 & 15.5.2.4 type compatibility.
171 // x.IsTkCompatibleWith(y) is true if "x => y" or passing actual y to
172 // dummy argument x would be valid. Be advised, this is not a reflexive
173 // relation. Kind type parameters must match.
174 bool IsTkCompatibleWith(const DynamicType &) const;
175
176 // Result will be missing when a symbol is absent or
177 // has an erroneous type, e.g., REAL(KIND=666).
178 static std::optional<DynamicType> From(const semantics::DeclTypeSpec &);
179 static std::optional<DynamicType> From(const semantics::Symbol &);
180
From(const A & x)181 template <typename A> static std::optional<DynamicType> From(const A &x) {
182 return x.GetType();
183 }
From(const A * p)184 template <typename A> static std::optional<DynamicType> From(const A *p) {
185 if (!p) {
186 return std::nullopt;
187 } else {
188 return From(*p);
189 }
190 }
191 template <typename A>
From(const std::optional<A> & x)192 static std::optional<DynamicType> From(const std::optional<A> &x) {
193 if (x) {
194 return From(*x);
195 } else {
196 return std::nullopt;
197 }
198 }
199
200 private:
201 // Special kind codes are used to distinguish the following Fortran types.
202 enum SpecialKind {
203 TypelessKind = -1, // BOZ actual argument to intrinsic function or pointer
204 // argument to ASSOCIATED
205 ClassKind = -2, // CLASS(T) or CLASS(*)
206 AssumedTypeKind = -3, // TYPE(*)
207 };
208
DynamicType()209 constexpr DynamicType() {}
210
211 TypeCategory category_{TypeCategory::Derived}; // overridable default
212 int kind_{0};
213 const semantics::ParamValue *charLength_{nullptr};
214 const semantics::DerivedTypeSpec *derived_{nullptr}; // TYPE(T), CLASS(T)
215 };
216
217 // Return the DerivedTypeSpec of a DynamicType if it has one.
218 const semantics::DerivedTypeSpec *GetDerivedTypeSpec(const DynamicType &);
219 const semantics::DerivedTypeSpec *GetDerivedTypeSpec(
220 const std::optional<DynamicType> &);
221 const semantics::DerivedTypeSpec *GetParentTypeSpec(
222 const semantics::DerivedTypeSpec &);
223
224 std::string DerivedTypeSpecAsFortran(const semantics::DerivedTypeSpec &);
225
226 template <TypeCategory CATEGORY, int KIND = 0> struct TypeBase {
227 static constexpr TypeCategory category{CATEGORY};
228 static constexpr int kind{KIND};
229 constexpr bool operator==(const TypeBase &) const { return true; }
GetTypeTypeBase230 static constexpr DynamicType GetType() { return {category, kind}; }
AsFortranTypeBase231 static std::string AsFortran() { return GetType().AsFortran(); }
232 };
233
234 template <int KIND>
235 class Type<TypeCategory::Integer, KIND>
236 : public TypeBase<TypeCategory::Integer, KIND> {
237 public:
238 using Scalar = value::Integer<8 * KIND>;
239 };
240
241 template <int KIND>
242 class Type<TypeCategory::Real, KIND>
243 : public TypeBase<TypeCategory::Real, KIND> {
244 public:
245 static constexpr int precision{common::PrecisionOfRealKind(KIND)};
246 static constexpr int bits{common::BitsForBinaryPrecision(precision)};
247 using Scalar = value::Real<value::Integer<bits>, precision>;
248 };
249
250 // The KIND type parameter on COMPLEX is the kind of each of its components.
251 template <int KIND>
252 class Type<TypeCategory::Complex, KIND>
253 : public TypeBase<TypeCategory::Complex, KIND> {
254 public:
255 using Part = Type<TypeCategory::Real, KIND>;
256 using Scalar = value::Complex<typename Part::Scalar>;
257 };
258
259 template <>
260 class Type<TypeCategory::Character, 1>
261 : public TypeBase<TypeCategory::Character, 1> {
262 public:
263 using Scalar = std::string;
264 };
265
266 template <>
267 class Type<TypeCategory::Character, 2>
268 : public TypeBase<TypeCategory::Character, 2> {
269 public:
270 using Scalar = std::u16string;
271 };
272
273 template <>
274 class Type<TypeCategory::Character, 4>
275 : public TypeBase<TypeCategory::Character, 4> {
276 public:
277 using Scalar = std::u32string;
278 };
279
280 template <int KIND>
281 class Type<TypeCategory::Logical, KIND>
282 : public TypeBase<TypeCategory::Logical, KIND> {
283 public:
284 using Scalar = value::Logical<8 * KIND>;
285 };
286
287 // Type functions
288
289 // Given a specific type, find the type of the same kind in another category.
290 template <TypeCategory CATEGORY, typename T>
291 using SameKind = Type<CATEGORY, std::decay_t<T>::kind>;
292
293 // Many expressions, including subscripts, CHARACTER lengths, array bounds,
294 // and effective type parameter values, are of a maximal kind of INTEGER.
295 using IndirectSubscriptIntegerExpr =
296 common::CopyableIndirection<Expr<SubscriptInteger>>;
297
298 // For each intrinsic type category CAT, CategoryTypes<CAT> is an instantiation
299 // of std::tuple<Type<CAT, K>> that comprises every kind value K in that
300 // category that could possibly be supported on any target.
301 template <TypeCategory CATEGORY, int KIND>
302 using CategoryKindTuple =
303 std::conditional_t<IsValidKindOfIntrinsicType(CATEGORY, KIND),
304 std::tuple<Type<CATEGORY, KIND>>, std::tuple<>>;
305
306 template <TypeCategory CATEGORY, int... KINDS>
307 using CategoryTypesHelper =
308 common::CombineTuples<CategoryKindTuple<CATEGORY, KINDS>...>;
309
310 template <TypeCategory CATEGORY>
311 using CategoryTypes = CategoryTypesHelper<CATEGORY, 1, 2, 3, 4, 8, 10, 16, 32>;
312
313 using IntegerTypes = CategoryTypes<TypeCategory::Integer>;
314 using RealTypes = CategoryTypes<TypeCategory::Real>;
315 using ComplexTypes = CategoryTypes<TypeCategory::Complex>;
316 using CharacterTypes = CategoryTypes<TypeCategory::Character>;
317 using LogicalTypes = CategoryTypes<TypeCategory::Logical>;
318
319 using FloatingTypes = common::CombineTuples<RealTypes, ComplexTypes>;
320 using NumericTypes = common::CombineTuples<IntegerTypes, FloatingTypes>;
321 using RelationalTypes = common::CombineTuples<NumericTypes, CharacterTypes>;
322 using AllIntrinsicTypes = common::CombineTuples<RelationalTypes, LogicalTypes>;
323 using LengthlessIntrinsicTypes =
324 common::CombineTuples<NumericTypes, LogicalTypes>;
325
326 // Predicates: does a type represent a specific intrinsic type?
327 template <typename T>
328 constexpr bool IsSpecificIntrinsicType{common::HasMember<T, AllIntrinsicTypes>};
329
330 // Predicate: is a type an intrinsic type that is completely characterized
331 // by its category and kind parameter value, or might it have a derived type
332 // &/or a length type parameter?
333 template <typename T>
334 constexpr bool IsLengthlessIntrinsicType{
335 common::HasMember<T, LengthlessIntrinsicTypes>};
336
337 // Represents a type of any supported kind within a particular category.
338 template <TypeCategory CATEGORY> struct SomeKind {
339 static constexpr TypeCategory category{CATEGORY};
340 constexpr bool operator==(const SomeKind &) const { return true; }
341 };
342
343 using NumericCategoryTypes = std::tuple<SomeKind<TypeCategory::Integer>,
344 SomeKind<TypeCategory::Real>, SomeKind<TypeCategory::Complex>>;
345 using AllIntrinsicCategoryTypes = std::tuple<SomeKind<TypeCategory::Integer>,
346 SomeKind<TypeCategory::Real>, SomeKind<TypeCategory::Complex>,
347 SomeKind<TypeCategory::Character>, SomeKind<TypeCategory::Logical>>;
348
349 // Represents a completely generic type (or, for Expr<SomeType>, a typeless
350 // value like a BOZ literal or NULL() pointer).
351 struct SomeType {};
352
353 class StructureConstructor;
354
355 // Represents any derived type, polymorphic or not, as well as CLASS(*).
356 template <> class SomeKind<TypeCategory::Derived> {
357 public:
358 static constexpr TypeCategory category{TypeCategory::Derived};
359 using Scalar = StructureConstructor;
360
SomeKind()361 constexpr SomeKind() {} // CLASS(*)
SomeKind(const semantics::DerivedTypeSpec & dts)362 constexpr explicit SomeKind(const semantics::DerivedTypeSpec &dts)
363 : derivedTypeSpec_{&dts} {}
SomeKind(const DynamicType & dt)364 constexpr explicit SomeKind(const DynamicType &dt)
365 : SomeKind(dt.GetDerivedTypeSpec()) {}
CONSTEXPR_CONSTRUCTORS_AND_ASSIGNMENTS(SomeKind)366 CONSTEXPR_CONSTRUCTORS_AND_ASSIGNMENTS(SomeKind)
367
368 bool IsUnlimitedPolymorphic() const { return !derivedTypeSpec_; }
GetType()369 constexpr DynamicType GetType() const {
370 if (!derivedTypeSpec_) {
371 return DynamicType::UnlimitedPolymorphic();
372 } else {
373 return DynamicType{*derivedTypeSpec_};
374 }
375 }
derivedTypeSpec()376 const semantics::DerivedTypeSpec &derivedTypeSpec() const {
377 CHECK(derivedTypeSpec_);
378 return *derivedTypeSpec_;
379 }
380 bool operator==(const SomeKind &) const;
381 std::string AsFortran() const;
382
383 private:
384 const semantics::DerivedTypeSpec *derivedTypeSpec_{nullptr};
385 };
386
387 using SomeInteger = SomeKind<TypeCategory::Integer>;
388 using SomeReal = SomeKind<TypeCategory::Real>;
389 using SomeComplex = SomeKind<TypeCategory::Complex>;
390 using SomeCharacter = SomeKind<TypeCategory::Character>;
391 using SomeLogical = SomeKind<TypeCategory::Logical>;
392 using SomeDerived = SomeKind<TypeCategory::Derived>;
393 using SomeCategory = std::tuple<SomeInteger, SomeReal, SomeComplex,
394 SomeCharacter, SomeLogical, SomeDerived>;
395
396 using AllTypes =
397 common::CombineTuples<AllIntrinsicTypes, std::tuple<SomeDerived>>;
398
399 template <typename T> using Scalar = typename std::decay_t<T>::Scalar;
400
401 // When Scalar<T> is S, then TypeOf<S> is T.
402 // TypeOf is implemented by scanning all supported types for a match
403 // with Type<T>::Scalar.
404 template <typename CONST> struct TypeOfHelper {
405 template <typename T> struct Predicate {
valueTypeOfHelper::Predicate406 static constexpr bool value() {
407 return std::is_same_v<std::decay_t<CONST>,
408 std::decay_t<typename T::Scalar>>;
409 }
410 };
411 static constexpr int index{
412 common::SearchMembers<Predicate, AllIntrinsicTypes>};
413 using type = std::conditional_t<index >= 0,
414 std::tuple_element_t<index, AllIntrinsicTypes>, void>;
415 };
416
417 template <typename CONST> using TypeOf = typename TypeOfHelper<CONST>::type;
418
419 int SelectedCharKind(const std::string &, int defaultKind);
420 int SelectedIntKind(std::int64_t precision = 0);
421 int SelectedRealKind(
422 std::int64_t precision = 0, std::int64_t range = 0, std::int64_t radix = 2);
423
424 // For generating "[extern] template class", &c. boilerplate
425 #define EXPAND_FOR_EACH_INTEGER_KIND(M, P, S) \
426 M(P, S, 1) M(P, S, 2) M(P, S, 4) M(P, S, 8) M(P, S, 16)
427 #define EXPAND_FOR_EACH_REAL_KIND(M, P, S) \
428 M(P, S, 2) M(P, S, 3) M(P, S, 4) M(P, S, 8) M(P, S, 10) M(P, S, 16)
429 #define EXPAND_FOR_EACH_COMPLEX_KIND(M, P, S) EXPAND_FOR_EACH_REAL_KIND(M, P, S)
430 #define EXPAND_FOR_EACH_CHARACTER_KIND(M, P, S) M(P, S, 1) M(P, S, 2) M(P, S, 4)
431 #define EXPAND_FOR_EACH_LOGICAL_KIND(M, P, S) \
432 M(P, S, 1) M(P, S, 2) M(P, S, 4) M(P, S, 8)
433 #define TEMPLATE_INSTANTIATION(P, S, ARG) P<ARG> S;
434
435 #define FOR_EACH_INTEGER_KIND_HELP(PREFIX, SUFFIX, K) \
436 PREFIX<Type<TypeCategory::Integer, K>> SUFFIX;
437 #define FOR_EACH_REAL_KIND_HELP(PREFIX, SUFFIX, K) \
438 PREFIX<Type<TypeCategory::Real, K>> SUFFIX;
439 #define FOR_EACH_COMPLEX_KIND_HELP(PREFIX, SUFFIX, K) \
440 PREFIX<Type<TypeCategory::Complex, K>> SUFFIX;
441 #define FOR_EACH_CHARACTER_KIND_HELP(PREFIX, SUFFIX, K) \
442 PREFIX<Type<TypeCategory::Character, K>> SUFFIX;
443 #define FOR_EACH_LOGICAL_KIND_HELP(PREFIX, SUFFIX, K) \
444 PREFIX<Type<TypeCategory::Logical, K>> SUFFIX;
445
446 #define FOR_EACH_INTEGER_KIND(PREFIX, SUFFIX) \
447 EXPAND_FOR_EACH_INTEGER_KIND(FOR_EACH_INTEGER_KIND_HELP, PREFIX, SUFFIX)
448 #define FOR_EACH_REAL_KIND(PREFIX, SUFFIX) \
449 EXPAND_FOR_EACH_REAL_KIND(FOR_EACH_REAL_KIND_HELP, PREFIX, SUFFIX)
450 #define FOR_EACH_COMPLEX_KIND(PREFIX, SUFFIX) \
451 EXPAND_FOR_EACH_COMPLEX_KIND(FOR_EACH_COMPLEX_KIND_HELP, PREFIX, SUFFIX)
452 #define FOR_EACH_CHARACTER_KIND(PREFIX, SUFFIX) \
453 EXPAND_FOR_EACH_CHARACTER_KIND(FOR_EACH_CHARACTER_KIND_HELP, PREFIX, SUFFIX)
454 #define FOR_EACH_LOGICAL_KIND(PREFIX, SUFFIX) \
455 EXPAND_FOR_EACH_LOGICAL_KIND(FOR_EACH_LOGICAL_KIND_HELP, PREFIX, SUFFIX)
456
457 #define FOR_EACH_LENGTHLESS_INTRINSIC_KIND(PREFIX, SUFFIX) \
458 FOR_EACH_INTEGER_KIND(PREFIX, SUFFIX) \
459 FOR_EACH_REAL_KIND(PREFIX, SUFFIX) \
460 FOR_EACH_COMPLEX_KIND(PREFIX, SUFFIX) \
461 FOR_EACH_LOGICAL_KIND(PREFIX, SUFFIX)
462 #define FOR_EACH_INTRINSIC_KIND(PREFIX, SUFFIX) \
463 FOR_EACH_LENGTHLESS_INTRINSIC_KIND(PREFIX, SUFFIX) \
464 FOR_EACH_CHARACTER_KIND(PREFIX, SUFFIX)
465 #define FOR_EACH_SPECIFIC_TYPE(PREFIX, SUFFIX) \
466 FOR_EACH_INTRINSIC_KIND(PREFIX, SUFFIX) \
467 PREFIX<SomeDerived> SUFFIX;
468
469 #define FOR_EACH_CATEGORY_TYPE(PREFIX, SUFFIX) \
470 PREFIX<SomeInteger> SUFFIX; \
471 PREFIX<SomeReal> SUFFIX; \
472 PREFIX<SomeComplex> SUFFIX; \
473 PREFIX<SomeCharacter> SUFFIX; \
474 PREFIX<SomeLogical> SUFFIX; \
475 PREFIX<SomeDerived> SUFFIX; \
476 PREFIX<SomeType> SUFFIX;
477 #define FOR_EACH_TYPE_AND_KIND(PREFIX, SUFFIX) \
478 FOR_EACH_INTRINSIC_KIND(PREFIX, SUFFIX) \
479 FOR_EACH_CATEGORY_TYPE(PREFIX, SUFFIX)
480 } // namespace Fortran::evaluate
481 #endif // FORTRAN_EVALUATE_TYPE_H_
482